Filters








354 Hits in 1.9 sec

Full Abstraction for Linda [chapter]

Cinzia Di Giusto, Maurizio Gabbrielli
2008 Lecture Notes in Computer Science  
This paper investigates full abstraction of a trace semantics for two Linda-like languages. The first language provides primitives for adding and removing messages from a shared memory, local choice, parallel composition and recursion. The second one adds the possibility of checking for the absence of a message in the store. After having defined a denotational semantics based on traces, we obtain fully abstract semantics for both languages by using suitable abstractions in order to identify
more » ... erent traces which do not correspond to different operational behaviours. Full Abstraction for Linda 79 traces. It can happen that these richer semantic structures "add too much" in the sense that the semantics · based on them allows to distinguish processes which have the same behaviour w.r.t. O(P ), under any possible context. In this case suitable abstractions must be used in · in order to obtain a fully abstract result which, in general, can be stated as follows: P = Q iff, for any context C [•], In this paper we investigate the full abstraction problem, as described above, for two variants of Linda. Linda is a programming paradigm [11] which allows interprocess communication through a shared data space, also called tuple space, where processes can post and retrieve messages (also called tuples). The shared memory paradigm offers some advantages since it decouples communication between processes: communication is in fact asynchronous and processes do not need to be aware of each other identity or location. Indeed, the Linda paradigm has received also a commercial interest, mainly due to the applications which use the Java Spaces from Sun Microsystems [10] and TSpaces from IBM [13] models, both based on Linda (a more detailed comparison of Linda implementations can be found in [19] ). Distributed Linda-like languages have also been investigated. Notably, Klaim [17] is an implemented language based on the Linda paradigm where the central store is replaced by several distributed local stores and processes mobility among different locations is supported. Fully abstract semantics based on traces for input/output observables have been studied many years ago for several concurrent languages, as we shall discuss in Section 6. However, to the best of our knowledge no one has yet addressed this problem for a Linda-like language. Many different formalizations and variants of Linda have been defined. Here we use essentially the process-algebraic formalization of Linda introduced in [6,7] and we consider the very basic Linda dialects. The first one, which we call Linda-core, apart from the usual operators in process algebra (choice, parallel composition, recursion) contains the two Linda primitives in and out which allow to remove and add messages to the store, respectively. For Linda-core we define a compositional, fixpoint trace semantics which is correct but not fully abstract when considering the input/output pairs. Hence we introduce a suitable abstraction on traces and show that this allows us to obtain a fully abstract semantics. The second dialect (Linda-inp) enriches the syntax of Linda-core by allowing also a construct (inp) which allows to check the absence of information in the store. We prove that in this case a much simpler abstraction on traces is sufficient to obtain a full abstraction result. This accounts for the augmented expressive power of the language with inp, which can be formally proven by using the techniques in [6, 20] . Unfortunately, due to the saturation operator, the fully abstract semantics are not compositional. This is unavoidable in our trace model, since the properties that we need to abstract depend on sets of traces (rather than on single ones). Of course this does not mean that in general a compositional fully abstract semantics based on traces does not exist. However, in case it existed, it would use traces substantially more complicated than ours. The remainder of the paper is organized as follows. Section 2 introduces the Linda languages under consideration while Section 3 defines their denotational semantics. We then provide the fully abstract semantics for the core language in Section 4. Section 5
doi:10.1007/978-3-540-78739-6_6 fatcat:6gbe45b6vzfublbq54vbvptjoi

Activity Networks with Delays An application to toxicity analysis [article]

Franck Delaplace, Cinzia Di Giusto, Jean-Louis Giavitto
2016 arXiv   pre-print
ANDy , Activity Networks with Delays, is a discrete time framework aimed at the qualitative modelling of time-dependent activities. The modular and concise syntax makes ANDy suitable for an easy and natural modelling of time-dependent biological systems (i.e., regulatory pathways). Activities involve entities playing the role of activators, inhibitors or products of biochemical network operation. Activities may have given duration, i.e., the time required to obtain results. An entity may
more » ... nt an object (e.g., an agent, a biochemical species or a family of thereof) with a local attribute, a state denoting its level (e.g., concentration, strength). Entities levels may change as a result of an activity or may decay gradually as time passes by. The semantics of ANDy is formally given via high-level Petri nets ensuring this way some modularity. As main results we show that ANDy systems have finite state representations even for potentially infinite processes and it well adapts to the modelling of toxic behaviours. As an illustration, we present a classification of toxicity properties and give some hints on how they can be verified with existing tools on ANDy systems. A small case study on blood glucose regulation is provided to exemplify the ANDy framework and the toxicity properties.
arXiv:1608.07440v1 fatcat:55iobpe66jbj3ej7agpayuuudu

On the k-synchronizability of systems [article]

Cinzia Di Giusto, Laetitia Laversa, Etienne Lozes
2020 arXiv   pre-print
In this paper, we work on the notion of k-synchronizability: a system is k-synchronizable if any of its executions, up to reordering causally independent actions, can be divided into a succession of k-bounded interaction phases. We show two results (both for mailbox and peer-to-peer automata): first, the reachability problem is decidable for k-synchronizable systems; second, the membership problem (whether a given system is k-synchronizable) is decidable as well. Our proofs fix several
more » ... issues in previous attempts to prove these two results for mailbox automata.
arXiv:1909.01627v2 fatcat:ytqzkbnwbzf4pins2upuneybe4

Adaptable Processes (Extended Abstract) [chapter]

Mario Bravetti, Cinzia Di Giusto, Jorge A. Pérez, Gianluigi Zavattaro
2011 Lecture Notes in Computer Science  
We propose the concept of adaptable processes as a way of overcoming the limitations that process calculi have for describing patterns of dynamic process evolution. Such patterns rely on direct ways of controlling the behavior and location of running processes, and so they are at the heart of the adaptation capabilities present in many modern concurrent systems. Adaptable processes have a location and are sensible to actions of dynamic update at runtime. This allows to express a wide range of
more » ... olvability patterns for processes. We introduce a core calculus of adaptable processes and propose two verification problems for them: bounded and eventual adaptation. While the former ensures that at most k consecutive errors will arise in future states, the latter ensures that if the system enters into an error state then it will eventually reach a correct state. We study the (un)decidability of these two problems in different fragments of the calculus. Rather than a specification language, our calculus intends to be a basis for investigating the fundamental properties of evolvable processes and for developing richer languages with evolvability capabilities.
doi:10.1007/978-3-642-21461-5_6 fatcat:rmuiuyb5vrdlbodnkaztz3x6dm

On the k-synchronizability of Systems [chapter]

Cinzia Di Giusto, Laetitia Laversa, Etienne Lozes
2020 Lecture Notes in Computer Science  
We study k-synchronizability: a system is k-synchronizable if any of its executions, up to reordering causally independent actions, can be divided into a succession of k-bounded interaction phases. We show two results (both for mailbox and peer-to-peer automata): first, the reachability problem is decidable for k-synchronizable systems; second, the membership problem (whether a given system is k-synchronizable) is decidable as well. Our proofs fix several important issues in previous attempts to prove these two results for mailbox automata.
doi:10.1007/978-3-030-45231-5_9 fatcat:dibv56v3c5fwfmyfv6aaa26clq

Expressiveness of Multiple Heads in CHR [chapter]

Cinzia Di Giusto, Maurizio Gabbrielli, Maria Chiara Meo
2009 Lecture Notes in Computer Science  
Constraint Handling Rules (CHR) are a committed-choice declarative language which has been designed for writing constraint solvers. A CHR program consists of multi-headed guarded rules which allow one to rewrite constraints into simpler ones until a solved form is reached. Many examples in the vast literature on the subject show that multiple heads are important in order to write programs which solve specific problems. On the other hand, the presence of multiples heads complicates considerably
more » ... he semantics. Therefore, since restricting to single head rules does not affect the Turing completeness of the language, one can legitimately ask whether multiple heads do indeed augment the expressive power of the language. In this paper we answer positively to this question by showing that, under certain reasonable assumptions, it is not possible to encode the CHR language (with multi-headed rules) into a single head language while preserving the intended meaning of programs.
doi:10.1007/978-3-540-95891-8_21 fatcat:sy2bolpwvrddri3gjdxt65hgza

Revisiting Glue Expressiveness in Component-Based Systems [chapter]

Cinzia Di Giusto, Jean-Bernard Stefani
2011 Lecture Notes in Computer Science  
doi:10.1007/978-3-642-21464-6_2 fatcat:6lpo2zmb3ngznmihpe6us72ov4

Systemic approach for toxicity analysis

Cinzia Di Giusto, Hanna Klaudel, Franck Delaplace
2014 Applications and Theory of Petri Nets  
A high-level Petri net framework is introduced for the toxic risk assessment in biological and bio-synthetic systems. Unlike empirical techniques mostly used in toxicology or toxicogenomics, we propose a systemic approach consisting of a series of behavioral rules (reactions) that depend on abstract discrete "expression" levels of involved agents (species). We introduce a finite state high-level Petri net model allowing exhaustive verification (model-checking) of properties related to
more » ... m alteration or appearing of hazardous behaviors. The approach is applied to the study of the impact of the aspartame assimilation into the blood glucose regulation process.
dblp:conf/apn/GiustoKD14 fatcat:lrx6kc5zcbevbprjcscw4kuxfe

Disciplined structured communications with disciplined runtime adaptation

Cinzia Di Giusto, Jorge A. Pérez
2015 Science of Computer Programming  
h i g h l i g h t s • A model of session communications with located and update processes. • A type discipline that ensures absence of communication errors and consistent updates. • Several examples of runtime adaptation in the typed process framework. a r t i c l e i n f o a b s t r a c t Session types offer a powerful type-theoretic foundation for the analysis of structured communications, as commonly found in service-oriented systems. They are defined upon core programming calculi which
more » ... only limited support for expressing requirements related to runtime adaptation. This is unfortunate, as service-oriented systems are increasingly being deployed upon highly dynamic infrastructures in which such requirements are central concerns. In previous work, we developed a process calculi framework of adaptable processes, in which concurrent processes can be replaced, suspended, or discarded at runtime. In this paper, we propose a session type discipline for a calculus with adaptable processes. Our typed framework offers a simple alternative for integrating runtime adaptation mechanisms in the modeling and analysis of structured communications. We show that well-typed processes enjoy safety and consistency properties: while the former property ensures the absence of communication errors at runtime, the latter guarantees that active session behavior is never disrupted by adaptation actions.
doi:10.1016/j.scico.2014.04.017 fatcat:wilyfeykc5hsxdhacvwgxlnka4

Adaptable processes

Mario Bravetti, Cinzia Di Giusto, Jorge Perez, Gianluigi Zavattaro, Matthew Hennessy
2012 Logical Methods in Computer Science  
We propose the concept of adaptable processes as a way of overcoming the limitations that process calculi have for describing patterns of dynamic process evolution. Such patterns rely on direct ways of controlling the behavior and location of running processes, and so they are at the heart of the adaptation capabilities present in many modern concurrent systems. Adaptable processes have a location and are sensible to actions of dynamic update at runtime; this allows to express a wide range of
more » ... olvability patterns for concurrent processes. We introduce a core calculus of adaptable processes and propose two verification problems for them: bounded and eventual adaptation. While the former ensures that the number of consecutive erroneous states that can be traversed during a computation is bound by some given number k, the latter ensures that if the system enters into a state with errors then a state without errors will be eventually reached. We study the (un)decidability of these two problems in several variants of the calculus, which result from considering dynamic and static topologies of adaptable processes as well as different evolvability patterns. Rather than a specification language, our calculus intends to be a basis for investigating the fundamental properties of evolvable processes and for developing richer languages with evolvability capabilities.
doi:10.2168/lmcs-8(4:13)2012 fatcat:uhh4rhg63jdnbiobwdqd4mdphi

Steps on the Road to Component Evolvability [chapter]

Mario Bravetti, Cinzia Di Giusto, Jorge A. Pérez, Gianluigi Zavattaro
2012 Lecture Notes in Computer Science  
We have recently developed a calculus for dynamically evolvable aggregations of components. The calculus extends CCS with primitives for describing components and their evolvability capabilities. Central to these novel primitives is a restricted form of higher-order communication of processes involved in update operations. The origins of our calculus for components can indeed be traced back to our own previous work on expressiveness and decidability results for core higher-order process
more » ... Here we overview these previous works, and discuss the motivations and design decisions that led us from higher-order process calculi to calculi for component evolvability. Supported by the EU integrated project HATS, the Fondation de Coopération Scientifique Digiteo Triangle de la Physique, and FCT / MCTES (CMU-PT/NGN44-2009-12) -INTERFACES
doi:10.1007/978-3-642-27269-1_19 fatcat:3zgdocpymfcfjowwayqahbtlji

On the Expressiveness of Forwarding in Higher-Order Communication [chapter]

Cinzia Di Giusto, Jorge A. Pérez, Gianluigi Zavattaro
2009 Lecture Notes in Computer Science  
In higher-order process calculi the values exchanged in communications may contain processes. There are only two capabilities for received processes: execution and forwarding. Here we propose a limited form of forwarding: output actions can only communicate the parallel composition of statically known closed processes and processes received through previously executed input actions. We study the expressiveness of a higher-order process calculus featuring this style of communication. Our main
more » ... ult shows that in this calculus termination is decidable while convergence is undecidable. P ::= a(x). P | a P | P P | x | 0 ( * ) An input prefixed process a(x). P can receive on name (or channel) a a process to be substituted in the place of x in the body P ; an output message a P can send P (the
doi:10.1007/978-3-642-03466-4_10 fatcat:64bvkinp3ze4vfpmw4izduwqhe

Event-based run-time adaptation in communication-centric systems

Cinzia Di Giusto, Jorge A. Pérez
2016 Formal Aspects of Computing  
This research was partially supported by a Short-Term Scientific Mission grant to Di Giusto from COST Action IC1201: Behavioural Types for Reliable Large-Scale Software Systems.  ... 
doi:10.1007/s00165-016-0377-z fatcat:dqiglmrt3ncovoc4bfepzx5xqi

A Categorical Theory of Patches

Samuel Mimram, Cinzia Di Giusto
2013 Electronical Notes in Theoretical Computer Science  
When working with distant collaborators on the same documents, one often uses a version control system, which is a program tracking the history of files and helping importing modifications brought by others as patches. The implementation of such a system requires to handle lots of situations depending on the operations performed by users on files, and it is thus difficult to ensure that all the corner cases have been correctly addressed. Here, instead of verifying the implementation of such a
more » ... stem, we adopt a complementary approach: we introduce a theoretical model, which is defined abstractly by the universal property that it should satisfy, and work out a concrete description of it. We begin by defining a category of files and patches, where the operation of merging the effect of two coinitial patches is defined by pushout. Since two patches can be incompatible, such a pushout does not necessarily exist in the category, which raises the question of which is the correct category to represent and manipulate files in conflicting state. We provide an answer by investigating the free completion of the category of files under finite colimits, and give an explicit description of this category: its objects are finite sets labeled by lines equipped with a transitive relation and morphisms are partial functions respecting labeling and relations.
doi:10.1016/j.entcs.2013.09.018 fatcat:3rvcfkb2bvcwji3gqkbjn62orq

On Recursion, Replication and Scope Mechanisms in Process Calculi [chapter]

Jesús Aranda, Cinzia Di Giusto, Catuscia Palamidessi, Frank D. Valencia
2007 Lecture Notes in Computer Science  
This paper we shall survey and discuss in detail the the work on the relative expressiveness of Recursion and Replication in various process calculi. Namely, CCS, the π-calculus, the Ambient calculus, Concurrent Constraint Programming and calculi for Cryptographic Protocols. We shall see that often the ability of expressing recursive behaviours via replication depends on the scoping mechanisms of the given calculus which compensate for the restriction of replication. The work of Jesús Aranda
more » ... been supported by COLCIENCIAS (Instituto Colombiano para el Desarrollo de la Ciencia y la Tecnología "Francisco José de Caldas") and ÉGIDE (Centre francais pour l'accueil et les echanges internationaux)
doi:10.1007/978-3-540-74792-5_9 fatcat:wwgm3df6h5b23puab6oog32dyu
« Previous Showing results 1 — 15 out of 354 results